Following these steps below to upload theme via FTP:
Step 1. Login your FTP account via an FTP software to access your host web server.
Step 2. Unzip sailing.zip file.
Step 3. Upload the exacted theme folder sailing to wp-content/ themes folder.
Step 4. Active the theme in Dashboard >> Appearance >> Themes.
Step 5. Enable Thim Core to activate the core of Sailing and start importing demo data process.